Yazar "Ozyurt, H" seçeneğine göre listele

Listeleniyor 1 - 7 / 7
  • Küçük Resim Yok
    Öğe
    Changes in oxidative status in silver nitrate induced corneal neovascularization.
    (Assoc Research Vision Ophthalmology Inc, 2000) Totan, Y; Aydin, E; Daglioglu, M; Ozyurt, H; Sogut, S
    [Abstract Not Available]
  • Küçük Resim Yok
    Öğe
    Concentrations of trace elements in larynx and skin tissues with epidermoid cancer
    (Dustri-Verlag Dr Karl Feistle, 2004) Kizilay, A; Kalcioglu, MT; Ozyurt, H; Vural, H; Sogut, S; Cokkeser, Y; Akyol, O
    Background and objectives: Playing a crucial role in a number of biological processes, trace elements are an essential part of the body. Up to now, trace elements-cancer relationships have not had a definitive explanation. This study was scheduled to investigate the trace element content of squamous cell carcinoma of the larynx and skin. Methods: The study was designed as a prospective controlled study. Tissue concentrations of iron, selenium, copper and zinc were studied in 30 patients with squamous cell carcinoma (19 larynx and 11 skin), while 20 tissues (12 larynx and 8 neck) of non-cancerous patients served as control. All samples were taken during surgical operations. Tissue element concentrations were measured by atomic absorption spectrophotometer after tissues were digested in an acid mixture. Results: No meaningful differences were interpreted in copper and zinc in epidermoid cancer and non-cancerous tissues. However, iron and selenium concentrations were found to be decreased significantly in cancer tissues than in control values. Conclusion: Decreased selenium and iron concentrations in the cancerous tissue from the patients with epidermoid cancer may result in increased oxidative stress because of the requirements of these elements for activities of some antioxidant enzymes.
  • Küçük Resim Yok
    Öğe
    The effects of erdosteine on the activities of some metabolic enzymes during cisplatin-induced nephrotoxicity in rats
    (Academic Press Ltd- Elsevier Science Ltd, 2004) Yilmaz, HR; Iraz, M; Sogut, S; Ozyurt, H; Yildirim, Z; Akyol, O; Gergerlioglu, S
    Cisplatin is one of the widely used chemothrapeutic agents. One of the major side effects of the drug is renal toxicity. The aims of the presented study was (1) to investigate the effect of cisplatin on some renal metabolic enzyme activities such as hexokinase (HK), glucose-6-phosphate dehydrogenase (G6PD), lactate dehydrogenase (LDH), and malate dehydrogenase (MDH) in an experimental model of acute renal failure and (2) to examine the protective role of erdosteine, an expectorant agent which has also antioxidant properties on cisplatin-induced nephrotoxicity and the enzyme activities mentioned above. Female Wistar albino rats were divided into three groups: sham operation group (n = 6). cisplatin group (n = 9), erdostein + cisplatin group (n = 8). All the chemicals used were applied intraperitoneally. Hexokinase, G6PD, LDH, and MDH activities were determined in the kidney supernatant at the end of the surgical procedures. Spectrophotometric methods were used to determine the activities of above-mentioned enzymes in the kidney tissue. Hexokinase and G6PD activities were found to be increased in cisplatin group compared to control group. G6PD activities were found to be decreased in erdosteine + cisplatin group compared to cisplatin group. There were minimal changes in LDH and MDH activities of the two study groups compared with the control group. The results obtained suggested that the glucose metabolizing metabolic pathways of renal tissue were partially affected from cisplatin toxicity and erdosteine have some protective effects on these enzyme activities. (C) 2004 Elsevier Ltd. All rights reserved.
  • Küçük Resim Yok
    Öğe
    The effects of ginkgo biloba extract on tissue adenosine deaminase, xanthine oxidase, myeloperoxidase, malondialdehyde, and nitric oxide in cisplatin-induced nephrotoxicity
    (Sage Publications Inc, 2006) Gulec, M; Iraz, M; Yilmaz, HR; Ozyurt, H; Temel, I
    This study was carried out to determine if Ginkgo Biloba Extract (GBE or Egb 761) exerts a beneficial effect against cisplatin-induced renal failure in rats. Sprague Dawley rats were divided into four groups. The first group (control) received orally 1 mL/kg/day of 0.9% saline by an oral carrier vehicle on days 1 to 10. The second group was injected with 7 mg/kg cisplatin intraperitoneally (i.p.) on the fourth day, once only. The third group (vit E + cisplatin) was administered 10 mg/kg/day i.p. vit E on 1 to 10 days with one dose of i.p. cisplatin (7 mg/kg) injection on the fourth day. The fourth group (GBE + cisplatin) was given GBE orally at 100 mg/mL/kg started on the first day up to the tenth day with one dose of cisplatin (7 mg/kg) injection on the fourth day. Cisplatin was found to lead a statistically significant increase in plasma BUN and creatinine levels, as well as urine micro total protein (MTP) levels, leading to acute renal failure (ARF) in rats. Renal xanthine oxidase (XO) activities increased in all groups (statistically significant in cisplatin + GBE-treated rats; P < 0.001). Adenosine deaminase (AD) activities were increased in cisplatin-treated rats, and decreased in cisplatin + GBE-treated (P < 0.041) and cisplatin + vit E-treated (P < 0.005) rats, compared to controls. Malondialdehyde (MDA), nitric oxide (NO) levels and myeloperoxidase (MPO) activities were increased in the kidney tissue of cisplatin-treated rats. Vit E improved plasma creatinine and urine MTP levels, together with tissue MDA, NO levels, and MPO activities. But GBE had no statistically significant effect on those parameters. These results indicate that increased XO, AD and MPO activities, as well as MDA and NO levels play a critical role in cisplatin nephrotoxicity. GBE has been shown to protect against cisplatin-induced nephrotoxicity.
  • Küçük Resim Yok
    Öğe
    Erdosteine prevents bleomycin-induced pulmonary fibrosis in rats
    (Elsevier, 2004) Sogut, S; Ozyurt, H; Armutcu, F; Kart, L; Iraz, M; Akyol, O; Ozen, S
    Oxidative stress plays an important role in the pathogenesis of idiopathic pulmonary fibrosis. Therefore, erdosteine, an antioxidant, is expected to have an inhibitor potential against the disease. Rats were given one dose of bleomycin in pulmonary fibrosis groups and saline in controls. The first dose of oral erdosteine (10 mg/kg/day) was given 2 days before the bleomycin injection to achieve the plateau level in blood and continued until killing. At day 14, fibrotic changes were evaluated, using Aschoft's criteria and lung hydroxyproline content. Bleomycin produced a fivefold increase in fibrosis score that was decreased by 87% by erdosteine (P>0.001) and almost twofold increases in hydroxyproline content which were completely prevented by erdosteine. Myeloperoxidase activities and MDA levels, which were significantly higher in the bleomycin group, were then significantly attenuated by erdosteine. These results revealed that oral erdosteine may prevent the development of acute pulmonary inflammation caused by bleomycin injection via the repression of neutrophil accumulation and lipid peroxidation, resulting in the inhibition of subsequent lung fibrosis. (C) 2004 Elsevier B.V. All rights reserved.
  • Küçük Resim Yok
    Öğe
    Oral erdosteine administration attenuates cisplatin-induced renal tubular damage in rats
    (Academic Press Ltd- Elsevier Science Ltd, 2003) Yildirim, Z; Sogut, S; Odaci, E; Iraz, M; Ozyurt, H; Kotuk, M; Akyol, O
    The effect of oral erdosteine on tissue malondialdehyde (MDA) and nitric oxide (NO) levels, and catalase (CAT), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities are investigated in the cisplatin model of acute renal failure in rats. A single dose of cisplatin caused kidney damage manifested by kidney histology as well as increases in plasma creatinine and blood urea nitrogen (BUN) levels. Treatment with free radical scavenger erdosteine attenuated increases in plasma creatinine and BUN, and tissue MDA and NO levels, and provided a histologically-proven protection against cisplatin-induced acute renal failure. Erdosteine also reduced depletion in the tissue CAT, GSH-Px, and SOD activities. These results show that erdosteine may be a promising drug for protection against cisplatin-induced nephrotoxicity. However, further studies with different doses of erdosteine are warranted for clarifying the issue. (C) 2002 Published by Elsevier Science Ltd.
  • Küçük Resim Yok
    Öğe
    Protective role of ?-tocopherol and caffeic acid phenethyl ester on ischemia-reperfusion injury via nitric oxide and myeloperoxidase in rat kidneys
    (Elsevier, 2004) Gurel, A; Armutcu, F; Sahin, S; Sogut, S; Ozyurt, H; Gulec, M; Kutlu, NO
    Background: The aim of this study was to determine the acute effects of antioxidant caffeic acid phenethyl ester (CAPE) and alpha-tocopherol (vitamin E) on nitric oxide (NO) production, neutrophil infiltration, and antioxidant enzyme activities on an in vivo model of renal ischemia-reperfusion injury. Methods: Rats were divided into five equal groups each consisting six rats: sham operation, ischemia, ischemia-reperfusion (I/R), I/R plus CAPE, and I/R plus vitamin E groups. CAPE or vitamin E was administered intraperitoneally before reperfusion. After experimental procedure, rats were sacrificed and both ipsilateral and contralateral kidneys were removed and prepared for NO concentrations, myeloperoxidase (MPO), catalase (CAT) and superoxide dismutase (SOD) activities. Results: Acute administration of vitamin E decreased NO concentrations in both ipsilateral and contralateral renal tissues compared to I/R group. SOD activity was increased in I/R and I/R + CAPE groups compared to sham operation group. The most prominent results were encountered in MPO activities, which did not change in contralateral kidneys in both ischemia and I/R groups. There was a significant decrease in ipsilateral MPO activity in ischemia group and a significant increase in I/R group compared to sham operation group. Pretreatment with intraperitoneal CAPE significantly diminished the tissue MPO activity indicating the prevention of the neutrophil sequestration into the kidney. Conclusion: There is a role for CAPE in attenuation in renal damage after I/R injury of the kidney, in part at least by inhibition of neutrophil sequestration. (C) 2003 Elsevier B.V. All rights reserved.